THE FIRST PHASE OF CONSTRUCTION OF A POLAROGRAPHIC OXYGEN VIBRATING PROBE HAS BEEN COMPLETED AND WE NOW HAVE A FUNCTIONAL PROTOTYPE SYSTEM WITH WHICH TO BEGIN TESTING THE PERFORMANCE OF OXYGEN MICRO-ELECTRODES IN AN ARTIFICIAL OXYGEN GRADIENT. ALTHOUGH THE SIGNAL OUTPUT FROM THE ELECTRODE IS STILL NOISY, WE HAVE BEEN ABLE TO MEASURE SUBSTANTIAL SIGNAL OFFSETS FROM BACKGROUND WHEN VIBRATING THE ELECTRODE IN AN ARTIFICIALLY GENERATED OXYGEN GRADIENT [IN TWO EXPERIMENTS, ~~V (BACKGROUND OXYGEN SOURCE) WAS +700~ V]. BASED ON THESE ENCOURAGING DATA, WE ARE NOW IN A POSITION TO START COLLECTING OXYGEN FLUX DATA AROUND ARTIFICIAL OXYGEN SOURCES AND SINKS, FOLLOWED SOON AFTER BY CHARACTERIZING THE SYSTEM ON A BIOLOGICAL MODEL (PROBABLY THE APLYSIA BAG CELL). AT PRESENT, WE ARE PURCHASING OXYGEN MICRO-ELECTRODES FROM DIAMOND GENERAL CORP (MI), BUT HOPE TO MANUFACTURE OUR OWN ELECTRODES IN THE FACILITY BEFORE LONG.